Good morning and welcome back! Yesterday I was so jazzed by the Boston Marathon news that I forgot to mention something: Axios has a bunch of smart, breezy newsletters on tech, health care, politics and business that you can sign up for here. They're free! Ok let's dive in . . .

Paris suspense builds

Still happening, eventually: In case you missed the Axios stream yesterday, a hotly anticipated White House meeting on the Paris climate accord didn't occur because, the administration said, key players were traveling with President Trump. "It will be scheduled at some point over the next couple of weeks," spokeswoman Sarah Sanders told reporters.

Sanders, on Air Force One, batted aside the suggestion that discord among top advisors about whether to withdraw from Paris was behind the scuttling of the meeting. "They wanted to have that conversation. Since they haven't had it, I don't think they could say that there's a lot of discord between where everyone is. And that's the purpose of the meeting," she said.

Filling the void: Well, nothing happened yesterday that could match the kinetic excitement of a (likely inconclusive) session of people sitting around a table talking about policy. But a couple things of note . . .

Some conservative House Republicans sent Trump a letter urging him to get out of Paris, including Reps. David McKinley and Paul Gosar, who posted it on his website. A dozen members signed the letter, according to Politico.

Why it matters: The low number of signatures signals that it's not a priority for many Republicans on Capitol Hill. "The constituency pushing that agenda is small, alienated, and getting less relevant by the day," one industry source tells Axios.

In contrast, there's wide support among GOP lawmakers and business groups aligned with fossil fuel companies and manufacturers for unwinding President Obama's domestic climate regulations, which the administration is pursuing with gusto.

What to watch, part 1: How many signatures Rep. Kevin Cramer eventually gets on a competing letter he's circulating for signatures. It argues for a separate path — staying in Paris but scaling back the Obama-era emissions pledge, defending U.S. fossil fuel sectors and promoting deployment of tech to capture carbon from burning coal.

What to watch, part 2: On Thursday, Trump will meet with Italian Prime Minister Paolo Gentiloni. The White House says the administration will reach its decision on Paris ahead of the G-7 summit in late May that Italy is hosting. It's possible they'll get a question about it at their joint press conference.

Recommended read: Vox has a good article that explores the repercussions of both abandoning Paris and staying in while seeking to scale back U.S. commitment. On the abandon side…

There's concern that some big developing nations where emissions are rising could scale back their efforts to rein them in. "If that were to happen, the chances of avoiding severe global warming would start to look far more dire."

"China, the world's largest emitter, would be poised to assume a dominant role in future talks, and its leaders have tended to argue for looser oversight and accountability mechanisms within the deal than the U.S. has."

From Amy's notebook: Forget King Coal, it's King Gas now

My colleague Amy Harder has a quick observation on some data that the Energy Department highlighted yesterday....

Natural gas is poised to be the top electricity source for the third straight summer this year, the Energy Information Administration said.

Why it matters: There's a saying that three makes a trend, and thus worth writing about. Natural gas has been creeping past coal in the U.S. electricity market for a few years now, fueled by plentiful supplies, cheaper prices and a cleaner profile. This latest data by the government shows how its market dominance is solidifying — no matter what the Trump administration does. For decades as the top U.S. power fuel, coal was dubbed King Coal, but the crown has now really been handed over to natural gas.

Sign of the times: Schlumberger, the big oilfield services provider, "recently opened an office on Sand Hill Road in the heart of Silicon Valley."

Solar: The National Renewable Energy Laboratory, an international team that includes Energy Department scientists, is out with a new paper in Science that explores the pathway for adding 5-10 terawatts of global solar photovoltaic capacity by 2030.

"Reaching that figure should be achievable through continued technology improvements and cost decreases, as well as the continuation of incentive programs to defray upfront costs of PV systems," an NREL summary states.

Lightning round

"He feels strongly enough about Tesla's potential in this industry that he downgraded shares of Paccar, a truck manufacturer, and Cummins, which makes engines, based partly on the threat from electric vehicles."

EVs: Speaking of Tesla, Bloomberg reports that Volkswagen is getting ready to challenge the Silicon Valley automaker with plans to unveil four "affordable" electric vehicles in the coming years, while its Audi division is readying an "upscale battery-powered crossover it aims to introduce in 2019."

Iran: The Associated Press reports that the Trump administration "notified Congress that Iran is complying with the terms of the 2015 nuclear deal negotiated by former President Barack Obama, and says the U.S. has extended the sanctions relief given to the Islamic republic in exchange for curbs on its atomic program."

Climate change: The New York Times magazine has a lengthy but highly readable look at the prospect of curbing global warming by spreading particles high in the atmosphere that reflect some solar energy away from the planet. It's pegged to the launch of Harvard's new Solar Geoengineering Research Program, which includes Bill Gates among its funders.

"The new Harvard program is not merely intent on getting its concepts out of the lab and into the field, though; a large share of its money will also be directed to physical and social scientists at the university, who will evaluate solar geoengineering's environmental dangers — and be willing to challenge its ethics and practicality."

More climate change: The Washington Post examines what a team of researchers are "describing as the first case of large-scale river reorganization as a result of human-caused climate change."

One cool thing

This is kind of like saying you just learned the Rolling Stones have some good songs, but whatever....The Interior Department's Instagram feed is featuring some lovely shots of U.S. national parks and monuments, like the photo above of Bryce Canyon in Utah posted a couple days ago. (Your Generate host is admittedly biased toward the National Parks as he was a short-order cook at the spectacular Mount Rainier National Park 24 years ago.)